How emissions charges and fuel-efficiency information are presented alter consumer car choices

One consequence of CO2-based emissions taxes has been an increase in popularity of diesel cars, which emit less CO2 but more nitrogen oxide (NOx) than petrol cars. NOx emissions, however, also contribute to climate change and have harmful consequences for public health, including increased risk of respiratory problems and dementia. We used an experiment to test (1) whether a NOx-based tax instrument would be likely to influence the type of car consumers choose, and (2) whether the presentation of the tax would alter its impact. In addition, since fuel efficiency has important implications for the environment and consumer finances, we also tested (3) whether the way fuel efficiency information is presented alters choices.